A vinyl chloride-based resin uses vinyl chloride, unsaturated carboxylic acid, and vinyl acetate as a monomer, and has excellent adherence to a metal material such as iron or aluminum, so it has been widely applied in fields of an ink binder and an adhesive. The vinyl chloride-based resin including carboxylic acid is generally used in China, the Middle East, India, etc., but when the resin is transported to the countries or stored for a long time under a high temperature and high humidity, the resin color is unfavorably changed into pink or red from the original white color. If the resin color is changed by heat during transportation or storage, the resin product value is lost, and the qualities such as adherence, solution discoloration, and the like may be deteriorated since the molecular structure is changed during the thermal discoloration.